1. Field of the Invention
This application relates to a device that will signal a malfunction in a toilet, and more particularly to a device that provides a reliable indication that the water level in a toilet tank has risen to the top of the overflow tube.
2. Description of the Related Art
A typical flush toilet is comprised of a toilet tank and a toilet bowl. The toilet tank contains water, which, when a flush handle is depressed, flows into the toilet bowl through a toilet tank drain hole. Prior art has disclosed several means of flushing water into the toilet bowl, the most standard including the flapper method. According to this method, pushing the flush handle of the toilet lifts a flapper valve, allowing water in the toilet tank to flow through the flush valve and into the toilet bowl. This water forces waste water in the toilet bowl through the main drain. When the tank is empty, the flapper valve seals the toilet tank drain hole, allowing another device to refill the tank.
The tank refilling is controlled by an on-off water shutoff valve with a valve gasket, controlled through lever action by a flotation device. When the tank is full, the water level forces a flotation device to a level such that it shuts off the water refilling the toilet tank.
A number of common problems can cause the shutoff valve to stay open after it should close. For example, the gasket is a wear item needing periodic replacement. The shutoff valve mechanism can become stuck, and the float can lose buoyancy over time.
In some municipal water systems, the water pressure rises considerably during off peak hours. Water system pressure can rise by 15 to 20 pounds per square inch (psi), and by as much as 30 psi in some situations. This rise in pressure could cause the water level in the tank to rise. If the normal water level in the tank is set too close to the top of the overflow tube, the toilet will leak water into the overflow tube during these off peak periods.
Water in excess of the normal tank-full water level enters an overflow tube, which is connected to the toilet bowl. Thus excess water in the toilet tank enters the toilet bowl directly through the overflow tube rather than spilling out of the tank onto the floor.
A water leak through the overflow tube can go undetected and account for significant water loss, especially if the shutoff valve leak is relatively slow and noiseless.
The objective of the present invention is to provide a reliable visual, audible or olfactory indication that the water is flowing from the toilet tank to the toilet bowl through the overflow tube.
Previous attempts to solve this problem have shortcomings that are overcome by the present invention.
One problem is that the moisture content of the air in the toilet tank is relatively high. Most devices that rely on the presence of water to activate a leak indicator will yield false positive indications since the atmospheric moisture will initiate the activation process. For instance, some have suggested coating the upper interior region of the overflow tube with a water soluble chemical that will release an indicator in the presence of water. But a false positive indication is likely due to the degradation of any moisture barrier with prolonged exposure to high levels of atmospheric moisture found in the toilet tank.
Another problem results from indicators, barriers or chemicals falling or being forced into the overflow tube causing constrictions in the flow of water from the overflow tube to the toilet bowl. This can result in a toilet malfunction.